This invention generally relates to compressors, and more particularly to a bootstrap method of loading a compressor having a blowoff valve which is spring loaded in a valve open position.
It is often necessary to unload or to de-pressurize a compressed air system, such as during periodic maintenance or during compressor shutdown. One method of unloading or de-pressurizing a compressed air system is by way of a blowoff valve. A type of blowoff valve, which typically is fail-safe during its operation in a compressor or a compressed air system, incorporates a design wherein a pneumatically controlled blowoff valve is spring loaded in a valve open position. A drawback associated with this type of blowoff valve design is that it must be pneumatically actuated to a closed position upon initial compressor start-up, however, at compressor start-up, typically there is insufficient compressed air pressure to pneumatically actuate the blowoff valve to the closed position.
Presently, in compressed air systems which employ these type of pneumatically controlled blowoff valves, at initial compressor start-up, these valves are actuated to a closed position by externally supplied compressed air, such as by plant or facility supplied compressed air. However, in a remote location, externally supplied compressed air typically is not available. Accordingly, despite the laudable fail-safe benefits of employing these types of blowoff valves, they are not useful in compressors which are employed in remote areas because there has not been an available method to pneumatically close these valves upon initial compressor start-up.
The foregoing illustrates limitations known to exist in present portable compressors. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.